The ecosocialist debates about strategy and tactics presented in this chapter focuses specifically on how these relate to ecosocialist contributions to furthering the aims of the radical climate justice movement. After a general overview of the kinds of issues generating discussion among ecosocialists, the ways in which debates about strategy and tactics unfold are illustrated with reference to three case studies. The first case study involves a debate about whether or not ecosocialists should support carbon trading as a means of reducing GHG emissions, the second case study discusses the reasoning underlying the decision of ecosocialist activists to support a strike by workers in the fossil fuel industry, and the third case study examines the debate between ecosocialists and climate justice activists in the wider climate justice movement on appropriate strategies and tactics to be adopted at the 2015 COP-21 climate negotiations in Paris. These debates were selected as foci because the first demonstrates ecosocialist views on market mechanisms (the ‘false solutions’/‘real solutions’ issue within the climate justice movement), the second demonstrates ecosocialist views about the role of the working class in struggles to mitigate and adapt to climate change, and the third demonstrates ecosocialist attitudes towards the formal climate change institutions and the extent to which their ideas influence the broader climate movement. The chapter includes a partial and transient evaluation of ecosocialist strengths and the challenges they face, and includes some comments about the role that prefiguration could potentially play in furthering the ecosocialist strategy of working towards ‘system change.’